Exmark NV730EKC48 Used Navigator Front Mount Mower Kohler ECV730 EFI. This item is Used, and has been refurbished for resale. The Exmark Navigator is a professional grade, zero-turn riding mower designed for superior lawn care. Combined with a larger diameter blower, the Navigator generates more airflow for better vacuuming and debris collection. The Navigator operates at a speed of up to 7mph, allowing users to handle their landscaping projects quickly and easily.